I have an old Walker electromagnet chuck and I really need some help figuring out how to wire this thing..

Digi-key and Mouser are also good for new components, but MPJA often has lots of surplus goodies
Also American Science and Surplus has some neat stuff
M
ps I recommend trying to find large transformers locally because of the high cost of shipping
 
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Hi Guys,

After sleeping on it and re-reading the OP, the thought occurs to me, if the original transformer is burnt out and so are the tube rectifiers, what caused that to happen ! The chances are that the magnetic chuck has shorted windings and unless it can be safely tested and rewound if it has, then whilst all the above information is correct, it could be for naught !
 
Just put a set of jumper cables off your car to it.
I will work enough to try it out.
 
I posted this in another thread but it will work for any high voltage DC load. Just substitute the mag chuck for the motor

These SCR dimmers are cheap as chips

Something like these

https://www.ebay.com.au/itm/KBPC501...ge/283172094480?hash=item41ee5f4210:rk:1:pf:0

https://www.ebay.com.au/itm/AC-50-2...h=item25f874b389:g:fncAAOSwdm1bFf-2:rk:2:pf:0



dc-motor-control-png.280342
 
Hi Guys,

After sleeping on it and re-reading the OP, the thought occurs to me, if the original transformer is burnt out and so are the tube rectifiers, what caused that to happen ! The chances are that the magnetic chuck has shorted windings and unless it can be safely tested and rewound if it has, then whilst all the above information is correct, it could be for naught !

Just put an ohm meter on the chuck

E=I/R so 110V / 10 amps = 11ohms (R)

Check the label on the chuck for its current rating and you should be able to determine what R the chuck should be
 
FYI, a typical 6x12" mag chuck draws about 125 watts at full saturation.
 
Light dimmers are designed for resistive (incandescent) loads, they may not last long with inductive loads like mag chucks.
Worth a try though, worst case you fry it and lose 6 or 7 bucks- no big deal
mark
 
Light dimmers are designed for resistive (incandescent) loads, they may not last long with inductive loads like mag chucks.
Worth a try though, worst case you fry it and lose 6 or 7 bucks- no big deal
mark

Ceiling fan controller maybe? They are designed for inductive loads.
 
Inductive loads with DC works exactly like a restive load until the power is switched off, then it will provide a back EMF depending on L and R (inductance and resistance) a flyback diode across the coil will fix this if it is an issue.
 
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